Water treatment method, water treatment system, denitrifying agent manufacturing method and denitrifying agent manufacturing equipment

摘要

To provide a water treatment method capable of controlling greenhouse gas emissions and capable of using existing equipment.SOLUTION: There is provided a water treatment method to add an organic carbon source and perform biological nitrification denitrification treatment, including: an oil layer separation step of separating an oil layer containing fatty acid from crude glycerin waste solution by-produced in primary production process of fatty acid alkyl ester made from fat and oil, to take out an aqueous layer containing glycerin; an alcohol separation step of separating monohydric alcohol from the aqueous layer taken out in the oil layer separation step; and a denitrification treatment step of adding the aqueous layer from which monohydric alcohol was separated in the alcohol separation step, as an organic carbon source for the biological nitrification and denitrification treatment.SELECTED DRAWING: Figure 2